Multiple chambers progress?


Hi I was wondering what the state of multi-chamber on a single arduino was? I saw references to that being started on but I’m not seeing anything in the documentation about how to get it working.

Right now I’ve got a single Arduino Uno and an 8x 10A SSR board and a bunch of ds18b20 temp sensors going into it. The Uno has enough pins to control the SSRs and the temp sensors come in on the onewire bus so it seems to me the only thing stopping this from being able to control 8 separate chambers is the multiple PID cycles being defined on the Uno… of course I have no idea how hard that would be to implement. So I’m just wondering if this setup is possible in perhaps a Dev build or if multiple chambers is only going to be supported on the Spark.

(also, for background, I want do to this because I’m building a Glycol Chiller to service multiple fermentors; I want one of the chambers to be a probe in the Glycol and SSR switching in “Fridge Constant Mode” or whatever to keep the Glycol at ~22F, and then another chamber setup with a probe in the thermowell, an SSR for cooling via a submersible pump circulating glycol in the jacketing, and an SSR for a heater attached to the vessel, and I want to use those to keep the beer at a profiled temp.)

So, what are my options right now?


Also here’s a quick look at the setup I’ve got so far with the arduino and SSRs; I’m not entirely sure if everything is correct I can’t tell which wire is supposed to be which on my ds18b20 sensors.


Hi @trimalchio!

Once we have brewpi-spark released with the brewpi touchscreen (v0.2.7) we will continue our development plans towards multi-chamber.

The code will be compatible between the arduino and the brewpi spark, although with the arduino having very limited resources, it’s unclear if it would be able to support 8 chambers.

The Photon (the successor to the Spark Core) is only weeks away from release and costs just $19 - it has many times the memory of the arduino, a much faster CPU, so that is the future for multi-chamber, and in fact all brewery control duties.


Looking for this support as well!

In the interim, my current chamber has 2 conicals in it, is there a way to add a Beer2 to the system to monitor both?



At present the way to monitor a 2nd conical is to setup a room temp sensor and use that to measure the 2nd conical.


mdma, monitoring can be done with anything, that shows temperature. :wink:
Controlling the second fermenter and its temperature is something I like to see implemented.


Sure! As do we - that’s a goal we are working towards!


I’m interested too :slight_smile:


Hello @mdma,

I am very new to this but I am currently about to do a build using RaspPi, Adrunio UNO, a 3.5" touch screen and I have an 8-channel relay. I will be just using it for 1 fermenting vessel for now as I know that is all the current BrewPi can handle but will I be required to obtain new hardware once the multi-fermenting vessel features are added? I guess I am trying to decide if I should just wait to build this or if I can go ahead and start now under the assumption it will be more of a software update thing.

Thanks a ton!



What kind of relay is it? Mechanical or SSR?




@bryancm1 that is a board of mechanical relays!

SSRs look like this:


See what I know!? I thought that board was a bunch of small SSRs. I used SSRs for my RIMS system so I have some passing knowledge.

So, I guess I still have the same question. I’m just wanting to start building this up with the hopes of eventually having control over 2 fermentation vessels (heat+cool) and one keezer (cool only). I am under the impression that can’t be done at this time due to software limitations. I have a Fermostat currently running one (that has some PID properties) and just a regular Johnson running the other. I love the idea of being able to monitor and alter programs over the network that’s why I wanted to get this going.


The reason I was asking is that you can’t connect a mechanical relay directly to the system since the relay coil usually draws too much current (iirc). Those relays look good since they’re meant for use with arduino.

The Brewpi Spark has 3/4 actuator outputs so will be no problem in software to drive additional relays later, such as direct beer heaters.


I’ve got my first beer fermenting with my BrewPi and I’ve come to the sad mathematical conclusion that I drink beer faster than I can ferment in my conical alone, thus I need to be able to move to carboys for secondary, which mean kicking the conical to self regulating status using a stainless coil and glycol. Thus, I’m super excited about getting the mutli ferment option going.

With that said, will it be possible to use the DS2408 chipset to control an 8 channel relay board to do the controlling? I would imagine so since the ball valve’s Elco is working on use that chipset, but I wanted to make sure before I invest.


I have been reading on your webpage and in this forum for few hours, trying to figure out the current state of the project. It is not easy to gather these informations at the moment. :wink: I am comming from the brewbit, since this project seems to be going down I decided that I wanna go with the BrewPi Spark.

  • The current spark is delivered with the Photon
  • The spark is currently usable for a single fermentation chamber or fridge, including a simple UI on the spark itself.
  • Basic PWN support for mashing has been implemented.

How far is the multichamper support? I saw the last software for the spark is 0.3.0 which brings basic pwm support. Is the multichamper feature soon to come or very low priority on your list? Due to the adress based approach with the sensors and actuators this should be a logic feature which I personally hope will be comming soon.

I hope you enjoyed your vacations!


Hi Patrick,

You have summarized it correctly.
Multi chamber support is not low priority, but it involves a lot of changes not just on the controller, but also in the web interface and data logging.

Instead of 3 fixed sensors, there are now a flexible number of sensors, which means multiple graphs, multiple controllers, multiple simultaneous brews, and a flexible dashboard to show them. This is the next big step in the software, but due to the changes on multiple levels not an easy one.

The hardware is capable of handling it and I am working on the software. The first step is to rewrite the software architecture on the embedded controller, which I have started already.

Cheers, Elco


Thank you for the insight Elco.

I am wondering what the exact approach is. Basically the Spark could control and endless number of sensors and actors if I got this right, so is the idea to have one Spark controlling multiple champers or is it thought that one has to get a Spark for every champer?

If I got this right, the raspberry will still be used as a sever, or would the Spark even replace the raspberry?

Is the idea in the future to allow multiple sparks which control multiple chambers to connect wirelessly to the raspberry-server? In my opinion this would give the gratest flexibility.

Can’t wait to get my Spark.


One Spark should be powerful enough to run multiple chambers, it is not powerful enough to run a database and web server.

In the future, all control will not be centered around chambers, but around PIDs.
Each PID takes a setpoint and a sensor as input, but they are mostly independent.

One fermentor could be 3 PIDs: one for heating, one for cooling and 1 to give a fridge set point from the beer temp.

Then you could have another 3 PIDs for a second chamber and 3 for your mash setup.

But it could be much simpler: one sensor, one heater, one setpoint, one PID.

Multiple beers in a single fridge could be:

  • 1 PID for beer 1 (heater)
  • 1 PID for beer 2 (heater)
  • 1 PID to cool the fridge
  • 1 PID to set the fridge setpoint (based both beers? Need to think about how this would work exactly)

So by making it just a list of PIDs, this could be very flexible.


Wow, this is exactly what I was hoping for. Thank you Elco, can’t wait for the update :wink:

My Spark will arrive today, the raspberry is already setup and waiting. Very very excited to get the first fridge up and running!

I want to be ready once the update arrives, so I already bought all the relais, expansion bords and sensors I will need in the future. I hooked up an expansion bord with a 10 meter long cable yesterday, on the expansion bord I connected two relais and 3 sensors. All devices show up on the webinterface. now I am excited for the future :+1: